Messages in this thread | | | Date | Thu, 10 Nov 2022 13:50:40 -0700 | From | Nathan Chancellor <> | Subject | Re: 回复 : [PATCH] locking: fix kernel/locking/ inline asm error |
| |
On Thu, Nov 10, 2022 at 06:05:13PM +0800, huyd12@chinatelecom.cn wrote: > > Thanks your comments, > And if any concern to apply it on upstream?
Unfortunately, I am not the one who gets to make that decision; one of the maintainers of this file will have to pick it up, assuming they see no issue with it.
Cheers, Nathan
> -----邮件原件----- > 发件人: nathan@kernel.org <nathan@kernel.org> > 发送时间: 2022年11月9日 6:40 > 收件人: guoj17@chinatelecom.cn > 抄送: peterz@infradead.org; mingo@redhat.com; will@kernel.org; > tglx@linutronix.de; bp@alien8.de; dave.hansen@linux.intel.com; > x86@kernel.org; longman@redhat.com; boqun.feng@gmail.com; linux-kernel@vger. > kernel.org; hpa@zytor.com; ndesaulniers@google.com; trix@redhat.com; > llvm@lists.linux.dev; huyd12@chinatelecom.cn > 主题: Re: [PATCH] locking: fix kernel/locking/ inline asm error > > On Tue, Nov 08, 2022 at 02:01:26PM +0800, guoj17@chinatelecom.cn wrote: > > From: Guo Jin <guoj17@chinatelecom.cn> > > > > When compiling linux 6.1.0-rc3 configured with CONFIG_64BIT=y and > > CONFIG_PARAVIRT_SPINLOCKS=y on x86_64 using LLVM 11.0, an error: > > "<inline asm> error: changed section flags for .spinlock.text, > > expected:: 0x6" occurred. > > > > The reason is the .spinlock.text in kernel/locking/qspinlock.o is used > > many times, but its flags are omitted in subsequent use. > > > > LLVM 11.0 assembler didn't permit to > > leave out flags in subsequent uses of the same sections. > > > > So this patch adds the corresponding flags to avoid above error. > > > > Signed-off-by: Guo Jin <guoj17@chinatelecom.cn> > > Right, my reverse bisect tells me that this error was fixed by [1] in LLVM, > which landed in 12.0.0 and was backported to LLVM 11.0.1 [2]. > > We could bump the minimum supported version of LLVM for building the kernel > to 11.0.1 over this, just to avoid further issues like this down the road, > as the kernel will always be adding new sections for various things. That > change would not appear to be disruptive, as all the major distros either > have 11.0.1 or newer or older than the current minimum of 11.0.0, so they > need to get clang from elsewhere already. > > archlinux:latest: clang version 14.0.6 > > debian:oldoldstable-slim: clang version 3.8.1-24 (tags/RELEASE_381/final) > debian:oldstable-slim: clang version 7.0.1-8+deb10u2 > (tags/RELEASE_701/final) > debian:stable-slim: Debian clang version 11.0.1-2 > debian:testing-slim: Debian clang version 14.0.6-2 > debian:unstable-slim: Debian clang version 14.0.6-7 > > fedora:35: clang version 13.0.1 (Fedora 13.0.1-1.fc35) > fedora:latest: clang version 14.0.5 (Fedora 14.0.5-1.fc36) > fedora:rawhide: clang version 15.0.4 (Fedora 15.0.4-1.fc38) > > opensuse/leap:15: clang version 13.0.1 > opensuse/leap:latest: clang version 13.0.1 > opensuse/tumbleweed:latest: clang version 15.0.3 > > ubuntu:bionic: clang version 6.0.0-1ubuntu2 (tags/RELEASE_600/final) > ubuntu:focal: clang version 10.0.0-4ubuntu1 > ubuntu:latest: Ubuntu clang version 14.0.0-1ubuntu1 > ubuntu:kinetic: Ubuntu clang version 15.0.2-1 > ubuntu:rolling: Ubuntu clang version 15.0.2-1 > ubuntu:devel: Ubuntu clang version 15.0.2-1 > > At the same time, you are clearly using LLVM 11.0.0, so I think this is a > reasonable fix in the immediate term. > > Reviewed-by: Nathan Chancellor <nathan@kernel.org> > > [1]: > https://github.com/llvm/llvm-project/commit/1deff4009e0ae661b03682901bf69322 > 97ce7ea1 > [2]: > https://github.com/llvm/llvm-project/commit/700baa009dc685a0adc5f94d258be4ae > 24742471 > > > --- > > arch/x86/include/asm/qspinlock_paravirt.h | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/arch/x86/include/asm/qspinlock_paravirt.h > > b/arch/x86/include/asm/qspinlock_paravirt.h > > index 60ece592b220..dbb38a6b4dfb 100644 > > --- a/arch/x86/include/asm/qspinlock_paravirt.h > > +++ b/arch/x86/include/asm/qspinlock_paravirt.h > > @@ -37,7 +37,7 @@ > __PV_CALLEE_SAVE_REGS_THUNK(__pv_queued_spin_unlock_slowpath, > ".spinlock.text"); > > * rsi = lockval (second argument) > > * rdx = internal variable (set to 0) > > */ > > -asm (".pushsection .spinlock.text;" > > +asm (".pushsection .spinlock.text, \"ax\";" > > ".globl " PV_UNLOCK ";" > > ".type " PV_UNLOCK ", @function;" > > ".align 4,0x90;" > > -- > > 2.25.1 > > >
| |